Signal transmission devices having a function of insulating input from output in power conversion circuits arid a function of transmitting signals have come to be used conventionally in power conversion circuits.
Signal transmission devices used in power conversion circuits for such a purpose include signal transmission devices, for instance as disclosed in PTL 1, that utilize a micro-transformer created on an integrated circuit. In the signal transmission circuit; device disclosed in PTL 1, a reception-side inductor is DC biased to ground voltage or to power-supply voltage. Among the positive and negative pulse voltages that are induced in the reception-side inductor only positive pulses are used in signal transmission.